[mirror_ubuntu-bionic-kernel.git] / drivers / media / rc / ir-sanyo-decoder.c

/* ir-sanyo-decoder.c - handle SANYO IR Pulse/Space protocol
 *
 * Copyright (C) 2011 by Mauro Carvalho Chehab <mchehab@redhat.com>
 *
 * This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation version 2 of the License.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 * This protocol uses the NEC protocol timings. However, data is formatted as:
 *	13 bits Custom Code
 *	13 bits NOT(Custom Code)
 *	8 bits Key data
 *	8 bits NOT(Key data)
 *
 * According with LIRC, this protocol is used on Sanyo, Aiwa and Chinon
 * Information for this protocol is available at the Sanyo LC7461 datasheet.
 */

#include <linux/bitrev.h>
#include "rc-core-priv.h"

#define SANYO_NBITS		(13+13+8+8)
#define SANYO_UNIT		562500  /* ns */
#define SANYO_HEADER_PULSE	(16  * SANYO_UNIT)
#define SANYO_HEADER_SPACE	(8   * SANYO_UNIT)
#define SANYO_BIT_PULSE		(1   * SANYO_UNIT)
#define SANYO_BIT_0_SPACE	(1   * SANYO_UNIT)
#define SANYO_BIT_1_SPACE	(3   * SANYO_UNIT)
#define SANYO_REPEAT_SPACE	(150 * SANYO_UNIT)
#define	SANYO_TRAILER_PULSE	(1   * SANYO_UNIT)
#define	SANYO_TRAILER_SPACE	(10  * SANYO_UNIT)	/* in fact, 42 */

enum sanyo_state {
	STATE_INACTIVE,
	STATE_HEADER_SPACE,
	STATE_BIT_PULSE,
	STATE_BIT_SPACE,
	STATE_TRAILER_PULSE,
	STATE_TRAILER_SPACE,
};

/**
 * ir_sanyo_decode() - Decode one SANYO pulse or space
 * @dev:	the struct rc_dev descriptor of the device
 * @duration:	the struct ir_raw_event descriptor of the pulse/space
 *
 * This function returns -EINVAL if the pulse violates the state machine
 */
static int ir_sanyo_decode(struct rc_dev *dev, struct ir_raw_event ev)
{
	struct sanyo_dec *data = &dev->raw->sanyo;
	u32 scancode;
	u8 address, not_address, command, not_command;

	if (!(dev->raw->enabled_protocols & RC_TYPE_SANYO))
		return 0;

	if (!is_timing_event(ev)) {
		if (ev.reset) {
			IR_dprintk(1, "SANYO event reset received. reset to state 0\n");
			data->state = STATE_INACTIVE;
		}
		return 0;
	}

	IR_dprintk(2, "SANYO decode started at state %d (%uus %s)\n",
		   data->state, TO_US(ev.duration), TO_STR(ev.pulse));

	switch (data->state) {

	case STATE_INACTIVE:
		if (!ev.pulse)
			break;

		if (eq_margin(ev.duration, SANYO_HEADER_PULSE, SANYO_UNIT / 2)) {
			data->count = 0;
			data->state = STATE_HEADER_SPACE;
			return 0;
		}
		break;


	case STATE_HEADER_SPACE:
		if (ev.pulse)
			break;

		if (eq_margin(ev.duration, SANYO_HEADER_SPACE, SANYO_UNIT / 2)) {
			data->state = STATE_BIT_PULSE;
			return 0;
		}

		break;

	case STATE_BIT_PULSE:
		if (!ev.pulse)
			break;

		if (!eq_margin(ev.duration, SANYO_BIT_PULSE, SANYO_UNIT / 2))
			break;

		data->state = STATE_BIT_SPACE;
		return 0;

	case STATE_BIT_SPACE:
		if (ev.pulse)
			break;

		if (!data->count && geq_margin(ev.duration, SANYO_REPEAT_SPACE, SANYO_UNIT / 2)) {
			if (!dev->keypressed) {
				IR_dprintk(1, "SANYO discarding last key repeat: event after key up\n");
			} else {
				rc_repeat(dev);
				IR_dprintk(1, "SANYO repeat last key\n");
				data->state = STATE_INACTIVE;
			}
			return 0;
		}

		data->bits <<= 1;
		if (eq_margin(ev.duration, SANYO_BIT_1_SPACE, SANYO_UNIT / 2))
			data->bits |= 1;
		else if (!eq_margin(ev.duration, SANYO_BIT_0_SPACE, SANYO_UNIT / 2))
			break;
		data->count++;

		if (data->count == SANYO_NBITS)
			data->state = STATE_TRAILER_PULSE;
		else
			data->state = STATE_BIT_PULSE;

		return 0;

	case STATE_TRAILER_PULSE:
		if (!ev.pulse)
			break;

		if (!eq_margin(ev.duration, SANYO_TRAILER_PULSE, SANYO_UNIT / 2))
			break;

		data->state = STATE_TRAILER_SPACE;
		return 0;

	case STATE_TRAILER_SPACE:
		if (ev.pulse)
			break;

		if (!geq_margin(ev.duration, SANYO_TRAILER_SPACE, SANYO_UNIT / 2))
			break;

		address     = bitrev16((data->bits >> 29) & 0x1fff) >> 3;
		not_address = bitrev16((data->bits >> 16) & 0x1fff) >> 3;
		command	    = bitrev8((data->bits >>  8) & 0xff);
		not_command = bitrev8((data->bits >>  0) & 0xff);

		if ((command ^ not_command) != 0xff) {
			IR_dprintk(1, "SANYO checksum error: received 0x%08Lx\n",
				   data->bits);
			data->state = STATE_INACTIVE;
			return 0;
		}

		scancode = address << 8 | command;
		IR_dprintk(1, "SANYO scancode: 0x%06x\n", scancode);
		rc_keydown(dev, scancode, 0);
		data->state = STATE_INACTIVE;
		return 0;
	}

	IR_dprintk(1, "SANYO decode failed at count %d state %d (%uus %s)\n",
		   data->count, data->state, TO_US(ev.duration), TO_STR(ev.pulse));
	data->state = STATE_INACTIVE;
	return -EINVAL;
}

static struct ir_raw_handler sanyo_handler = {
	.protocols	= RC_TYPE_SANYO,
	.decode		= ir_sanyo_decode,
};

static int __init ir_sanyo_decode_init(void)
{
	ir_raw_handler_register(&sanyo_handler);

	printk(KERN_INFO "IR SANYO protocol handler initialized\n");
	return 0;
}

static void __exit ir_sanyo_decode_exit(void)
{
	ir_raw_handler_unregister(&sanyo_handler);
}

module_init(ir_sanyo_decode_init);
module_exit(ir_sanyo_decode_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
MODULE_DESCRIPTION("SANYO IR protocol decoder");
Commit	Line	Data
b32e7243 MCC	1	/* ir-sanyo-decoder.c - handle SANYO IR Pulse/Space protocol
	2	*
	3	* Copyright (C) 2011 by Mauro Carvalho Chehab <mchehab@redhat.com>
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation version 2 of the License.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* This protocol uses the NEC protocol timings. However, data is formatted as:
	15	* 13 bits Custom Code
	16	* 13 bits NOT(Custom Code)
	17	* 8 bits Key data
	18	* 8 bits NOT(Key data)
	19	*
	20	* According with LIRC, this protocol is used on Sanyo, Aiwa and Chinon
	21	* Information for this protocol is available at the Sanyo LC7461 datasheet.
	22	*/
	23
	24	#include <linux/bitrev.h>
	25	#include "rc-core-priv.h"
	26
	27	#define SANYO_NBITS (13+13+8+8)
	28	#define SANYO_UNIT 562500 /* ns */
	29	#define SANYO_HEADER_PULSE (16 * SANYO_UNIT)
	30	#define SANYO_HEADER_SPACE (8 * SANYO_UNIT)
	31	#define SANYO_BIT_PULSE (1 * SANYO_UNIT)
	32	#define SANYO_BIT_0_SPACE (1 * SANYO_UNIT)
	33	#define SANYO_BIT_1_SPACE (3 * SANYO_UNIT)
	34	#define SANYO_REPEAT_SPACE (150 * SANYO_UNIT)
	35	#define SANYO_TRAILER_PULSE (1 * SANYO_UNIT)
	36	#define SANYO_TRAILER_SPACE (10 * SANYO_UNIT) /* in fact, 42 */
	37
	38	enum sanyo_state {
	39	STATE_INACTIVE,
	40	STATE_HEADER_SPACE,
	41	STATE_BIT_PULSE,
	42	STATE_BIT_SPACE,
	43	STATE_TRAILER_PULSE,
	44	STATE_TRAILER_SPACE,
	45	};
	46
	47	/**
	48	* ir_sanyo_decode() - Decode one SANYO pulse or space
	49	* @dev: the struct rc_dev descriptor of the device
	50	* @duration: the struct ir_raw_event descriptor of the pulse/space
	51	*
	52	* This function returns -EINVAL if the pulse violates the state machine
	53	*/
	54	static int ir_sanyo_decode(struct rc_dev *dev, struct ir_raw_event ev)
	55	{
	56	struct sanyo_dec *data = &dev->raw->sanyo;
	57	u32 scancode;
	58	u8 address, not_address, command, not_command;
	59
	60	if (!(dev->raw->enabled_protocols & RC_TYPE_SANYO))
	61	return 0;
	62
	63	if (!is_timing_event(ev)) {
	64	if (ev.reset) {
65	IR_dprintk(1, "SANYO event reset received. reset to state 0\n");
66	data->state = STATE_INACTIVE;
67	}
68	return 0;
69	}
70
71	IR_dprintk(2, "SANYO decode started at state %d (%uus %s)\n",
72	data->state, TO_US(ev.duration), TO_STR(ev.pulse));
73
74	switch (data->state) {
75
76	case STATE_INACTIVE:
77	if (!ev.pulse)
78	break;
79
80	if (eq_margin(ev.duration, SANYO_HEADER_PULSE, SANYO_UNIT / 2)) {
81	data->count = 0;
82	data->state = STATE_HEADER_SPACE;
83	return 0;
84	}
85	break;
86
87
88	case STATE_HEADER_SPACE:
89	if (ev.pulse)
90	break;
91
92	if (eq_margin(ev.duration, SANYO_HEADER_SPACE, SANYO_UNIT / 2)) {
93	data->state = STATE_BIT_PULSE;
94	return 0;
95	}
96
97	break;
98
99	case STATE_BIT_PULSE:
100	if (!ev.pulse)
101	break;
102
103	if (!eq_margin(ev.duration, SANYO_BIT_PULSE, SANYO_UNIT / 2))
104	break;
105
106	data->state = STATE_BIT_SPACE;
107	return 0;
108
109	case STATE_BIT_SPACE:
110	if (ev.pulse)
111	break;
112
113	if (!data->count && geq_margin(ev.duration, SANYO_REPEAT_SPACE, SANYO_UNIT / 2)) {
114	if (!dev->keypressed) {
115	IR_dprintk(1, "SANYO discarding last key repeat: event after key up\n");
116	} else {
117	rc_repeat(dev);
118	IR_dprintk(1, "SANYO repeat last key\n");
119	data->state = STATE_INACTIVE;
120	}
121	return 0;
122	}
123
124	data->bits <<= 1;
125	if (eq_margin(ev.duration, SANYO_BIT_1_SPACE, SANYO_UNIT / 2))
126	data->bits \|= 1;
127	else if (!eq_margin(ev.duration, SANYO_BIT_0_SPACE, SANYO_UNIT / 2))
128	break;
129	data->count++;
130
131	if (data->count == SANYO_NBITS)
132	data->state = STATE_TRAILER_PULSE;
133	else
134	data->state = STATE_BIT_PULSE;
135
136	return 0;
137
138	case STATE_TRAILER_PULSE:
139	if (!ev.pulse)
140	break;
141
142	if (!eq_margin(ev.duration, SANYO_TRAILER_PULSE, SANYO_UNIT / 2))
143	break;
144
145	data->state = STATE_TRAILER_SPACE;
146	return 0;
147
148	case STATE_TRAILER_SPACE:
149	if (ev.pulse)
150	break;
151
152	if (!geq_margin(ev.duration, SANYO_TRAILER_SPACE, SANYO_UNIT / 2))
153	break;
154
155	address = bitrev16((data->bits >> 29) & 0x1fff) >> 3;
156	not_address = bitrev16((data->bits >> 16) & 0x1fff) >> 3;
157	command = bitrev8((data->bits >> 8) & 0xff);
158	not_command = bitrev8((data->bits >> 0) & 0xff);
159
160	if ((command ^ not_command) != 0xff) {
161	IR_dprintk(1, "SANYO checksum error: received 0x%08Lx\n",
162	data->bits);
163	data->state = STATE_INACTIVE;
164	return 0;
165	}
166
167	scancode = address << 8 \| command;
168	IR_dprintk(1, "SANYO scancode: 0x%06x\n", scancode);
169	rc_keydown(dev, scancode, 0);
170	data->state = STATE_INACTIVE;
171	return 0;
172	}
173
174	IR_dprintk(1, "SANYO decode failed at count %d state %d (%uus %s)\n",
175	data->count, data->state, TO_US(ev.duration), TO_STR(ev.pulse));
176	data->state = STATE_INACTIVE;
177	return -EINVAL;
178	}
179
180	static struct ir_raw_handler sanyo_handler = {
181	.protocols = RC_TYPE_SANYO,
182	.decode = ir_sanyo_decode,
183	};
184
185	static int __init ir_sanyo_decode_init(void)
186	{
187	ir_raw_handler_register(&sanyo_handler);
188
189	printk(KERN_INFO "IR SANYO protocol handler initialized\n");
190	return 0;
191	}
192
193	static void __exit ir_sanyo_decode_exit(void)
194	{
195	ir_raw_handler_unregister(&sanyo_handler);
196	}
197
198	module_init(ir_sanyo_decode_init);
199	module_exit(ir_sanyo_decode_exit);
200
201	MODULE_LICENSE("GPL");
202	MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
203	MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
204	MODULE_DESCRIPTION("SANYO IR protocol decoder");